Using more than one SICStus runtime in a process is only supported when
the dynamic library version of the SICStus runtime is used (e.g.
An application that wants to use more than one SICStus runtime needs to
be built using the --multi-sp-aware option to spld. C-code
spld --multi-sp-aware will have the C preprocessor macro
MULTI_SP_AWARE defined and non-zero.
Unlike the single runtime case described above, an application built with --multi-sp-aware will not have a global variable that holds the dispatch vector. Instead, your code will have to take steps to ensure that the appropriate dispatch vector is used when switching between SICStus runtimes.
There are several steps needed to access a SICStus runtime from an application built with --multi-sp-aware.
SP_get_dispatch(). Note that this function is special in that it is not accessed through the dispatch vector; instead, it is exported in the ordinary manner from the SICStus runtime dynamic library (
sprt4-2-3.dllunder Windows and, typically,
SICStusDISPATCHVARexpands to something that references the dispatch vector obtained in step 1.
The C pre-processor macro
SICStusDISPATCHVAR should expand to a
SICSTUS_API_STRUCT_TYPE *, that is, a pointer to the dispatch
vector that should be used. When --multi-sp-aware is not used
SICStusDISPATCHVAR expands to
described above. When using --multi-sp-aware it is
probably best to let
SICStusDISPATCHVAR expand to a local
SP_load_sicstus_run_time()to load additional runtimes.
SICSTUS_API_STRUCT_TYPE *SP_get_dispatch(void *reserved);
SP_get_dispatch() returns the dispatch vector of the SICStus
runtime. The argument
reserved should be
function can be called from any thread.
typedef SICSTUS_API_STRUCT_TYPE *SP_get_dispatch_type(void *); int SP_load_sicstus_run_time(SP_get_dispatch_type **ppfunc, void *reserved);
SP_load_sicstus_run_time() loads a new SICStus
If a new runtime could be loaded a
positive value is returned and the address of the
SP_get_dispatch() function of the newly loaded SICStus runtime
is stored at the address
ppfunc. The second argument,
phandle, is reserved and should be
As a special case, if
SP_load_sicstus_run_time() is called from a
SICStus runtime that has not been initialized (with
SP_initialize()) and that has not previously been loaded as the
result of calling
SP_load_sicstus_run_time(), no new runtime
is loaded. Instead, the
SP_get_dispatch() of the runtime itself is
returned. In particular, the first time
is called on the initial SICStus runtime, and if this happens before
the initial SICStus runtime is initialized, no new runtime is
SP_load_sicstus_run_time() from a particular runtime can
be done from any thread.
An application that links statically with the SICStus runtime should
You should not use pre-linked foreign resources when using multiple SICStus runtimes in the same process.
For an example of loading and using multiple SICStus runtimes, see library/jasper/spnative.c that implements this functionality for the Java interface Jasper.